package com.takeeasy.platform.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

public class CipherUtil {

	private final static String[] hexDigits = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

	/** 对字符串进行MD5加密 */
	public static String encodeByMD5(String originString) {
		if (originString != null) {
			try {
				MessageDigest md = MessageDigest.getInstance("MD5");
				// 使用指定的字节数组对摘要进行最后更新，然后完成摘要计算
				byte[] results = md.digest(originString.getBytes());
				// 将得到的字节数组变成字符串返回
				String resultString = byteArrayToHexString(results);
				// String pass = resultString.toUpperCase();
				String pass = resultString;
				return pass;
			} catch (Exception ex) {
				ex.printStackTrace();
			}
		}
		return null;
	}

	private static String byteArrayToHexString(byte[] b) {
		StringBuffer resultSb = new StringBuffer();
		for (int i = 0; i < b.length; i++) {
			resultSb.append(byteToHexString(b[i]));
		}
		return resultSb.toString();
	}

	/** 将一个字节转化成十六进制形式的字符串 */
	private static String byteToHexString(byte b) {
		int n = b;
		if (n < 0)
			n = 256 + n;
		int d1 = n / 16;
		int d2 = n % 16;
		return hexDigits[d1] + hexDigits[d2];
	}

	public static String SHA1(String inStr) {
		MessageDigest md = null;
		String outStr = null;
		try {
			md = MessageDigest.getInstance("SHA-1"); // 选择SHA-1，也可以选择MD5
			byte[] digest = md.digest(inStr.getBytes()); // 返回的是byet[]，要转化为String存储比较方便
			outStr = byteToString(digest);
		} catch (NoSuchAlgorithmException nsae) {
			nsae.printStackTrace();
		}
		return outStr;
	}

	private static String byteToString(byte[] digest) {
		StringBuilder sbDes = new StringBuilder();
		String tmp = null;
		for (int i = 0; i < digest.length; i++) {
			tmp = (Integer.toHexString(digest[i] & 0xFF));
			if (tmp.length() == 1) {
				sbDes.append("0");
			}
			sbDes.append(tmp);
		}
		return sbDes.toString();
	}

	public static void main(String[] args) {
		System.out.println(SHA1("1text"));
	}
}
